Barbed suture line and preparation method thereof

Abstract

The invention provides a barb suture line and a preparation method thereof, and relates to the field of surgery and medical cosmetology, the preparation method of the barb suture line comprises the following steps: S1, extruding a thin-wall hollow tube through an extruder; s2, hot cutting is conducted on the pipe wall of the hollow pipe, and barbs are formed; and S3, cutting is conducted in the axis direction of the hollow pipe, and a kerf belt which does not penetrate through the pipe wall is formed. According to the preparation method of the barbed suture line, the thin-wall hollow pipe is obtained through extrusion molding, then thermal cutting is performed to form the barbs on the pipe wall, and the kerf belt is formed through non-through cutting in the axis direction, so that the suture line has better flexibility, the barbs generated by thermal cutting enhance the anchoring force, and the suture line is more flexible. The stability of the suture line in tissues is ensured; in addition, due to the non-through design of the kerf belt, the ductility of the suture line is improved, the suture line can adapt to tissue activity, the possibility of breakage is reduced, and therefore the reliability and the clinical effect of the suture line are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of surgery and medical cosmetology, in particular to a barbed suture and a preparation method thereof. BACKGROUND

[0002] Surgical barbed sutures are widely used because they do not require knotting and can generate bidirectional or unidirectional self-locking anchoring in tissues. The common preparation paths of existing products include: mechanical / laser cutting of solid monofilaments to form barbs, or segmented design of bidirectional barbs to adapt to different suture scenarios, and some documents also propose forming a sheath layer or coating sheet outside the core material, and then opening hooks on the outer layer to control the geometry and surface properties of the barbs.

[0003] However, the existing hook-opening schemes based on solid monofilaments have some technical challenges. One of them is that after forming the barbs, the overall bending and torsional stiffness of the line body tends to increase, which leads to insufficient compliance of the line body when the line needs to be bent, pass through a catheter or a puncture cannula, affecting the flexibility of the operation and the suture effect. In addition, in order to obtain a more uniform distribution of barbs in the circumference, twisting and heat setting of the monofilament can improve the distribution of the barbs, but during the clinical traction process, it is easy to superimpose a net torque, causing the line body to self-torsion and folding, thereby affecting the stability and reliability of the suture line. SUMMARY

[0004] To solve the problem of insufficient flexibility of the barbed suture in the existing technology in the tissue, the present application provides a barbed suture and a preparation method thereof. By extruding a thin-walled hollow tube, then performing hot cutting to form barbs on the tube wall, and forming a slit belt by non-through cutting along the axial direction, the suture has better flexibility, the barbs generated by hot cutting enhance the anchoring force, and the stability of the suture in the tissue is ensured. In addition, the non-through design of the slit belt increases the ductility of the suture, so that it can adapt to tissue activity and reduce the possibility of rupture, thereby improving the reliability and clinical effect of the suture.

[0005] The technical scheme adopted by the present application to solve its technical problems is: A preparation method of a barbed suture, characterized in that it comprises the following steps: S1: extruding a thin-walled hollow tube through an extruder; S2: performing hot cutting on the wall of the hollow tube to form barbs; S3: cutting along the axial direction of the hollow tube to form a slit belt that does not penetrate the wall.

[0006] Optionally, the hollow tube is extruded from a thermoplastic polymer.

[0007] Optionally, the ratio of the wall thickness to the outer diameter of the hollow tube is 0.10-0.15.

[0008] Optionally, the machining temperature of the hot cutting is higher than the glass transition temperature of the thermoplastic polymer and lower than the melting point thereof.

[0009] Optionally, the lifting angle between the barb and the hollow tube axis is 20-45°.

[0010] Optionally, the residual wall thickness at the cut slit zone is 0.30-0.50 of the wall thickness.

[0011] Optionally, the cut slit zone is obtained by vertical cutting with axial feed and radial feed.

[0012] Optionally, after the hollow tube is prepared in step S1, the method further comprises stretching and orienting the hollow tube.

[0013] Optionally, the ratio of the distance between adjacent cuts on the cut slit zone to the outer diameter of the hollow tube is 4-6.

[0014] Another object of the present application is to provide a barbed suture prepared by the preparation method of the barbed suture as described above.

[0015] The present application has the following advantages: The barbed suture and the preparation method thereof provided by the present application form barbs on the thin-walled hollow tube by hot cutting, and form a cut slit zone in the axial direction by non-through cutting, which significantly improves the overall performance and flexibility of the suture. Specifically, the present application manufactures a hollow tube with a thin wall thickness by an extruder, which effectively reduces the weight of the suture and improves its adaptability in complex tissue structures, thereby significantly improving the flexibility and reducing the potential damage to the tissue. Meanwhile, the present application forms barbs on the hollow tube wall by hot cutting, which ensures that the small barbs are cut off and accurately lifted and shaped at the same time, ensuring that the barbs provide effective anchoring in the tissue and improving the functionality of the suture. In addition, by performing deep non-through cutting on the tube wall, an intermittent weak point is formed, which significantly enhances the ductility and flexibility of the suture, effectively avoids the distortion effect caused by the rigidity of the material, and thereby improves the reliability and service life of the suture. BRIEF DESCRIPTION OF DRAWINGS

[0016] The present application will be further described below in conjunction with the drawings and examples.

[0017] Figure 1 is the preparation flowchart of the barbed suture in the present application. DETAILED DESCRIPTION

[0018] The application will be further described in detail. The examples described below are exemplary and are intended to explain the application, and cannot be understood as a limitation of the application, all other examples obtained by those skilled in the art based on the examples of the application without creative labor belong to the protection scope of the application.

[0019] In order to make the above-mentioned purposes, features and advantages of the application more obvious and easy to understand, the specific embodiments of the application are described in detail below with reference to the drawings.

[0020] In order to solve the problem of insufficient flexibility of the barbed suture in the tissue in the prior art, the application provides a preparation method of the barbed suture, comprising the following steps: S1: extruding a thin-walled hollow tube through an extruder; S2: performing hot cutting on the wall of the hollow tube to form a barb; and S3: cutting along the axial direction of the hollow tube to form a non-through wall cutting seam belt.

[0021] The barbed suture and the preparation method thereof provided by the application form a barb on the wall of the thin-walled hollow tube through hot cutting, and form a cutting seam belt through non-through cutting along the axial direction, which significantly improves the overall performance and flexibility of the suture. Specifically, the thin-walled hollow tube is manufactured by the extruder, which effectively reduces the weight of the suture and improves the adaptability of the suture in complex tissue structures, thereby significantly improving the flexibility and reducing the potential damage to the tissue. Meanwhile, the hot cutting technology is used to form the barb on the wall of the hollow tube, which ensures that the small barbs are cut off, lifted and shaped accurately, and ensures that the barb provides effective anchoring in the tissue and improves the functionality of the suture. In addition, the deep non-through cutting on the wall forms an intermittent weak point, which significantly enhances the ductility and flexibility of the suture, effectively avoids the distortion effect caused by the rigidity of the material, and improves the reliability and service life of the suture.

[0022] Preferably, the hollow tube is made of a thermoplastic polymer; further, the thermoplastic polymer is polydioxanone (PDO), and the polymer particles are injected at the melting temperature of the PDO to manufacture a uniform hollow tube by using the extrusion molding technology, which ensures the uniformity and consistency of the material.

[0023] In order to maximize the flexibility of the suture while ensuring that the suture has sufficient mechanical strength, the ratio of the wall thickness to the outer diameter of the hollow tube is preferably 0.10-0.15, which avoids structural instability and processing defects such as barb breakage or root tearing that can be caused by an excessively thin wall thickness, while preventing the rigidity of the suture caused by an excessively thick wall thickness, ensuring its adaptability and flexibility during surgical operation. In addition, this design reduces damage to the surrounding tissue, which is beneficial to reducing postoperative inflammatory response, thereby improving the healing quality and comfort of the patient, and significantly improving the practicability and clinical application value of the suture.

[0024] The processing temperature of the hot cutting is preferably higher than the glass transition temperature of the thermoplastic polymer and lower than the melting point thereof; further, the processing temperature of the hot cutting is preferably 85-90℃, which can more cleanly cut the polymer material, ensure the formation of the barb while accurately lifting and shaping it, and form an effective hooking barb structure; further, the lifting angle between the barb and the axis of the hollow tube is preferably 20-45°, which can avoid material cracking or the generation of internal stress microcracks, ensure seamless transition and metallurgical bonding strength between the barb root and the matrix, and eliminate the risk of delamination of the barb from the interface.

[0025] Further, the residual wall thickness at the suture band is preferably 0.30-0.50 times the wall thickness, so that the suture of the present application has excellent ductility, effectively prevents the occurrence of the twisting effect, and further allows the suture of the present application to stretch appropriately when subjected to tensile force, reducing stress concentration and the possibility of breakage; this is because when the residual wall thickness is less than 0.30 times the wall thickness, the risk of stress concentration and crack propagation at the root of the cut increases, and the fatigue life is shortened; and when it exceeds 0.50 times, the suture is too rigid to adapt to tissue deformation, increasing the risk of structural failure.

[0026] The suture band is preferably obtained by vertical cutting with axial feed and radial feed; which ensures the accuracy and consistency of the cut, not only realizes the uniform distribution of the suture band, but also helps to uniformly disperse stress throughout the suture, thereby enhancing the ductility and anti-twisting performance of the suture. At the same time, the clear cut produced by vertical cutting reduces burrs and debris, further improving the surface quality and overall functionality of the suture.

[0027] The ratio of the distance between adjacent cuts on the cutting strip to the outer diameter of the hollow tube is preferably 4-6 to ensure that there is a long enough section of uncut material between adjacent cuts, which is crucial for maintaining the key performance of the suture. Firstly, this section of intact material is the main part of the axial tensile force, and its length is crucial to meet the crack arrest requirement, so as to ensure that even if there are multiple cuts, the overall tensile strength of the suture will not be significantly reduced; secondly, it helps to maintain the continuity and hoop stiffness of the tube blank, avoiding the suture becoming too soft as a whole due to too dense cuts, and losing the ability to pass through the tissue. Among them, the distance between adjacent cuts on the cutting strip refers to the distance between the center lines of two adjacent cuts in the axial direction of the hollow tube of the suture.

[0028] In order to improve the mechanical properties of the suture, including tensile strength and elastic modulus, so that it is more suitable for bearing the tensile force in the operation, the present application preferably comprises a stretching orientation treatment step for the hollow tube after the hollow tube is prepared in step S1.

[0029] Another object of the present application is to provide a barbed suture prepared by the preparation method of the barbed suture as described above.

[0030] The barbed suture prepared by the present application effectively avoids the common interlayer separation problem of traditional composite structure sutures by using extrusion molding technology to manufacture a thin-walled hollow tube as a base material. Secondly, compared with the larger wall thickness and insufficient flexibility of the tubular blank manufactured by the traditional method, the suture of the present application exhibits significant flexibility and ductility, and can better adapt to the movement of the tissue and reduce the damage to the tissue. At the same time, by accurately controlling the ratio of wall thickness to outer diameter and the design of the cutting strip, the adaptability of the suture of the present application to the movement of the tissue is further enhanced.

[0031] In addition, the barb formed on the tube wall by the hot cutting technology in the present application realizes complete integration with the base material. This integrated structure significantly improves the anchoring strength of the barb, thereby enhancing the stability of the suture; reasonable residual wall thickness and cut spacing design also helps to evenly distribute stress and reduce stress concentration, effectively improving the fatigue resistance and impact resistance of the suture; and by designing the cut layout, the anti-kinking ability is further enhanced, ensuring high reliability and effectiveness in clinical application.

[0032] Based on the above ideal embodiments according to the present application, through the above description, relevant personnel can make various changes and modifications without deviating from the scope of the technical idea of the present application. The technical scope of the present application is not limited to the contents in the specification, and the technical scope must be determined according to the scope of claims.

Claims

1. A method of making a barbed suture, characterized by, The method comprises the following steps: S1: extruding a thin-walled hollow tube through an extruder; S2: performing hot cutting on the wall of the hollow tube to form barbs; S3: cutting along the axial direction of the hollow tube to form a non-through wall slit band.

2. The method for preparing the barbed suture as described in claim 1, characterized in that, The hollow tube is extruded from a thermoplastic polymer.

3. The method for preparing the barbed suture as described in claim 2, characterized in that, The ratio of the wall thickness to the outer diameter of the hollow tube is 0.10-0.

15.

4. The method for preparing the barbed suture as described in claim 2, characterized in that, The processing temperature of the hot cutting is higher than the glass transition temperature of the thermoplastic polymer and lower than the melting point thereof.

5. The method for preparing the barbed suture as described in claim 1, characterized in that, The lifting angle between the barb and the axial line of the hollow tube is 20-45°.

6. The method of claim 3, wherein the barbed suture is prepared by the steps of: The residual wall thickness at the slit band is 0.30-0.50 of the wall thickness.

7. The method for preparing the barbed suture as described in claim 6, characterized in that, The slit band is obtained by vertical cutting with axial feed and radial feed.

8. The method for preparing the barbed suture as described in claim 1, characterized in that, After the hollow tube is prepared in step S1, the method further comprises stretching and orienting the hollow tube.

9. The method for preparing the barbed suture as described in claim 1, characterized in that, The ratio of the distance between adjacent slits on the slit band to the outer diameter of the hollow tube is 4-6.

10. A barbed suture, characterized by, The barbed suture is prepared by the method of any one of claims 1-9.

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